Mango ring nematode

Systematic position: Hemicriconemoides mangiferae belongs to the phylum Nematoda, order Tylenchida, and family Criconematidae. These microscopic ectoparasitic nematodes are widely distributed in warm climates, often causing significant stress to various perennial plant species.

Affected crops: While primarily known as a pest of mango (Mangifera indica), this species exhibits a broad host range. It is frequently detected in the rhizosphere of litchi, various citrus species, vineyards, and several ornamental plants, thriving particularly well in sandy and sandy-loam soil textures.

Biology and life cycle: The nematode spends its entire life cycle in the soil surrounding the root zone. It undergoes a life cycle consisting of an egg stage, four larval stages, and an adult stage. The speed of development is highly temperature-dependent, allowing for multiple generations per year under tropical conditions, which leads to exponential population growth.

Damage and economic impact: Hemicriconemoides mangiferae feeds ectoparasitically by piercing root cortical cells with its long stylet. This feeding process causes necrosis of root tips, pruning of secondary roots, and creates entry points for secondary fungal and bacterial pathogens. Symptoms include stunted growth, chlorosis, reduced fruit yield, and general tree decline.

Control measures: Management of this pest requires an integrated pest management (IPM) approach to minimize soil contamination and population density. Recommended strategies include:

• Using clean, nematode-free planting stock from certified nurseries.
• Implementing regular soil sampling to monitor nematode density.
• Applying specific nematicides where permitted and necessary.
• Enhancing soil biological activity by adding organic matter and compost, which can suppress nematode activity.